Hunt for carjackers after assault, freeway chase

South Australian police are investigating a crime spree involving carjackings, high-speed pursuits, an assault and a break-in.

They think two, posssibly three, offenders stole a Renault from Mawson Lakes in northern Adelaide, later broke into a Birdwood service station in the Adelaide hills and then stole a BMW near Palmer, hitting a man on the head with a bottle.

He needed stitches for the gash.

The Renault is now burnt-out and may have been torched.

The BMW was chased by police until it crashed into a tree at Monarto South, near Murray Bridge.

Police say the offenders fled.

A four-wheel-drive was stolen at Monarto a short time later and there was another police chase into Mount Barker and along the South Eastern Freeway.

The stolen vehicle reversed into a police car and may have hit other cars on the freeway as it drove toward Adelaide.

The Land Cruiser, registration number WUH-692, was last seen being driven toward the northern suburbs.